ABSTRACT
The aim of present study was to estimate the total phenolic and flavonoid contents and to investigate in vitro antioxidant potential of methanolic leaf and root extracts of the herb, Hypochaeris radicata L. (Asteraceae). Antioxidant activity was assessed by using 2,2- diphenyl-1-picryl-hydrazyl (DPPH•) assay, reducing power activity, [2,2’-azino-bis(3- ethylbenzthiazoline-6-sulphonic acid)] ABTS•+ assay and ferrous ion chelating activity. Here, butylated hydroxytoluene (BHT), ascorbic acid (ASA), trolox and EDTA were used as standard antioxidants. The total phenolic and flavonoid contents were also determined and expressed in gallic acid and quercetin equivalent respectively. The results of the study indicate that the methanolic extracts of the leaf and root of H. radicata posses significant scavenging activity against DPPH• (97.99% for leaf and 96.44% for root at 250μg/ml each) and ferrous ions chelating activity (38.69% for leaf and 40.52% for root at 5000μg/ml each), reducing power activity (1.38 absorbance at 600μg/ml for leaf, 0.45 absorbance at 700 μg/ml for root) and free radical scavenging activity (ABTS•+) (2706.73 for leaf and 2028.37μmol for root TE/g). The free radical scavenging and antioxidant activities may be attributed to the presence of adequate phenolic (gallic acid content is 125.5μg/10mg in leaf and 133.06μg/10mg in root) and flavonoid compounds (105.76μg/2mg in leaf and 55.16μg/2mg in root). This study revealed that the methanolic extracts of both leaf and root of H. radicata has demonstrated significant antioxidant activity.
ABSTRACT
Plant phenolics constitute one of the major groups of components that act as primary antioxidant free radical terminators. This paper reports the antioxidative activity of methanolic and water extract of Nepeta nepetella. Phytochemical screening of the crude extracts of stems, leaves and flowers revealed the presence of different kind of chemical groups such as flavonoids, tannins, alkaloids, saponins and carbohydrates. The amounts of total phenolics solvent extracts (methanol and water extract) for the three parts of plant were determined spectrometrically. From the analyses, leaves methanolic extract had the highest total phenolic content (58.11± 1.24 mg GAE/g), the highest DPPH scavenging ability with the lowest IC50 value (1.45 ± 0.07 mg/ml), the same tendency was observed with ferric reducing power. Concerning β-carotene bleaching assays results showed that the stems methanolic extract exhibited the highest antioxidant ability with an IC50 higher than standards (0.148 ± 0.003 mg/ml).
ABSTRACT
Mushrooms collected from Deogyu mountain, Korea, in 2011, were identified as four classes, four orders, 13 families, 22 genera, and 33 species. In particular, agaricales was most abundant and comprised more than 70%. Their antioxidant activities were estimated using three different bioassay methods, the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical scavenging assay, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, and reducing power assay. As a result, the methanol extracts of Stereum ostrea, Laetiporus sulphureus var. miniatus, and Tyromyces sambuceus exhibited potent antioxidant activity in all bioassays tested.